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How blocks are chained in a blockchain
21–30 of 35 posts
Re: How blocks are chained in a blockchain
#22Re: How blocks are chained in a blockchain
#23Re: How blocks are chained in a blockchain
#24Earlier quoted context omitted.
The partial collision is easy to verify but hard to generate, consensus is defined as "longest chain is the source of truth". If some p2p node can present you a longer chain you switch your source of truth to that one.
In terms of Bitcoin consensus, it is actually the chain with the most work, not the longest chain.
Isn't the longest chain assumed to be the chain with the most work? Not an expert.
Re: How blocks are chained in a blockchain
#25Earlier quoted context omitted.
In terms of Bitcoin consensus, it is actually the chain with the most work, not the longest chain.
Isn't the longest chain assumed to be the chain with the most work? Not an expert.
Generally, yes. But remember that there are difficulty adjustments, and it's conceivable that there are two chains, one being a bit shorter but with higher difficulty, and that can have precedence over the longer but easier one. The point is that you want the chain embodying most work, no matter how long.
(And note that a) the difficulty is included in the header that gets hashed, and b) it is easy to check that the block conforms to the specified difficulty.)
That's why "heavier-chain-rule" would be a better name than "longest-chain-rule", strictly speaking.
Re: How blocks are chained in a blockchain
#26Earlier quoted context omitted.
I'd say the majority of the modern non-fork networks don't use proof of work and sha256. I'm on a team building one at the moment and we're using sha3.sum512 and no proof of work for production. Some "blockchains" aren't even blockchains of sequential blocks, they are forest DAGs of just transactions. I think the author's heart is in the right place and I'm thankful that it's being discussed on HN, as blockchain disc…
Cool, is it open sourced? how are you guys achieving consensus for different nodes? DHT over gossip protocol? Just thought Nostr over BitTorrent and/or tor network night be a good way to go.
It's not open source, we use a system that is similar to delegated proof of stake with a deterministic leader selection algorithm. dht via libp2p.
Bittorrent would be a cool way to do it. The trials I've seen with other networks over tor work in practice, however, its more fit for slower proof of work block driven networks with slower block times and less expectation for fast finality.
The shift away from PoW is largely driven by the need/expectation for semi-instant finality, which isn't feasible in 1st generation networks, systems where your transaction goes to a tx pool, waits for fee market acceptance, and then is mined into a block in an interval based in minutes with multiple confirms needed. There are pros and cons and use cases for both strategies, however the trend in defi, which is our niche, is finality in under a second, so that's the motivator behind that design decision. It's not without its faults, you're trading mining and difficulty adjustment algorithms for deterministic leader selection and absence/latency plans.
Re: How blocks are chained in a blockchain
#27Earlier quoted context omitted.
"The" blockchain is still "a" blockchain. There are many possible blockchain instantiations and Bitcoin is one of them.
Literally anyone can make up a Blockchain. That's why there's a convoluted mess of crypto.
This is true in theory, but to make anything novel with any viability is a long and unclear process.
Re: How blocks are chained in a blockchain
#28Earlier quoted context omitted.
Blockchain and smart contracts.
There's certainly application outside of currencies. Bluesky/atproto for example is built on DIDs (decentralised IDs) and IPLD (the data format/standard of IPFS). Both are very heavily rooted in cryptocurrency tech. There's a joke in the atproto community that it's a blockchain but without the currency because of this.
Neither DID nor IPLD have anything to do with cryptocurrency from a technical perspective. At least no more than do X.509 and ssh.
Re: How blocks are chained in a blockchain
#29Earlier quoted context omitted.
Literally anyone can make up a Blockchain. That's why there's a convoluted mess of crypto.
This is true in theory, but to make anything novel with any viability is a long and unclear process.
And more importantly, zero purpose other than to enrich themselves.
Re: How blocks are chained in a blockchain
#30Earlier quoted context omitted.
There's certainly application outside of currencies. Bluesky/atproto for example is built on DIDs (decentralised IDs) and IPLD (the data format/standard of IPFS). Both are very heavily rooted in cryptocurrency tech. There's a joke in the atproto community that it's a blockchain but without the currency because of this.
Neither DID nor IPLD have anything to do with cryptocurrency from a technical perspective. At least no more than do X.509 and ssh.
IPLD is literally a merkle tree data structure format standardised by IPFS which is heavily rooted in cryptocurrency and in fact has its own cryptocurrency created by the IPFS devs: Filecoin.
DIDs were created by cryptocurrency orgs. The standard was created by a bunch of cryptocurrency groups working with the W3C and the entire time it was being developed, it was derided by non-cryptocurrency people as just another way for cryptocurrency to scam people. It doesn't stop being related to cryptocurrency once you realise it's useful.